Image recording member

ABSTRACT

An image recording member for facsimiles, and so on, wherein the electrically conductive agent to be used for the recording layer as the active component of the recording member comprises a porous compound containing therein a polar substance. An image is recorded on this image recording member by causing electric current to flow through the recording layer by way of a recording needle.

United States Patent [191 Takatori et al.

1 IMAGE RECORDING MEMBER [75] Inventors: Yasushi Takatori, Machida;

Masahiro Hnruta, Funabashi; Akemi Shimozawa, Tokyo; Katsuhiko Nishide, Yokohama, all of Japan [73] Assignee: Canon Kabushiki Kaisha, Tokyo,

Japan [22] Filed: June 21, 1974 [21] Appl. No.: 481,789

[30] Foreign Application Priority Data July 6, 1973 Japan... 48-76708 July 6, 1973 Japan.... 48-76707 June 25, 1973 Japan... 48-71888 June 25, 1973 Japan 48-71887 June 22, 1973 Japan 48-70557 June 22, 1973 Japan .1 48-70556 [52] US. Cl 204/2; 117/367 [51] Int. Cl. B21H 1/20; 841C 3/08 [58] Field of Search .I 204/2; 346/76 R, 135;

[4 1 Aug. 26, 1975 [56] References Cited UNITED STATES PATENTS 2,967,784 H1961 Newman et a1 117/368 3,306,763 2/1967 Hoge A ll7/36.7 3,789,425 1/1974 Matsushimam, 346/135 3,792,481 2/1974 Nagashima et al 346/76 R Primary Examiner-T. M. Tufariello Attorney, Agent, or Firm-Fitzpatrick, Celia, Harper & Scinto [57] ABSTRACT An image recording member for facsimiles, and so on, wherein the electrically conductive agent to be used for the recording layer as the active component of the recording member comprises a porous compound containing therein a polar substance. An image is recorded on this image recording member by causing electric current to flow through the recording layer by way of a recording needle.

27 Claims, 3 Drawing Figures 1 IMAGE RECORDING MEMBER BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to image recording members which are capable of recording images by electrical expedient, and are therefore useful in recording various receiving signals such as those from facsimile, outputs from computers and their terminal equipments, data of various kinds of measuring apparatuses for industrial. medical. business and varieties of purposes.

2. Description of the Prior Art Recording of electrical signals as an image has been increasing year by year with development in the facsimile and other telecommunication devices. The methods which have so far been adapted most widely for such recording purposes may be represented by electrical discharge recording. electrolytic recording, and so forth.

The electrical discharge recording method is to form an image either by placing a white pigment layer on an electrically conductive black layer, or by placing an electrically conductive thin metal layer such as, for example, aluminum on the abovementioned electrically conductive black layer. and then by perforating the surface layer ofthe white pigment or the thin metal layer by electrical discharge ofa recording needle (hereinafter referred to as stylus) so as to remove the surface layer and to expose the black layer underneath thereof.

On the other hand. the electrolytic recording method is to form an image by first impregnating a sheet of paper with an electrolytic solution to bring the same into a wet state, and then causing electric current to flow therethrough by way of the stylus. The resulting image is either a colored substance formed by reaction between the ionized metal constituting the stylus and the electrolyte, or a colored decomposition product formed by electrolysis of the electrolyte impregnated in the paper by electric current caused to flow therethrough from the stylus.

According to the electric discharge recording method, as the surface layer is perforated by heat of electrical discharge generated by the stylus, there inevitably takes place various inconveniences such that very strong irritating odor comes out, dust from perforation of the surface layer scatters, wear and tear of the stylus are considerable, and other disadvantages. Moreover, mechanical forces such as folding, pressure adhesion, etc. to be imparted to the laminated layers are liable to expose the black layer with the consequence that the paper becomes easily stained. In another aspect, since the surface layer is made thin so as to facilitate the electric discharge, the black layer beneath the surface layer cannot be masked perfectly. which is liable to make the base color of the recording paper to assume grey rather than white. thereby worsening the outer appearance thereof.

On the other hand, since the electrolytic recording method is of the wet type, the recording paper is inferior in its preservability and the quality of the image formed thereon is deteriorated by running of the electrolyte. In addition, the paper undergoes deformation such as wrinkles caused on its surface due to drying after the image recording. These disadvantages are fatal to such a wet type recording method.

Also, in Japanese Pat. Nos. 22341/1963 and 29630/l969. there is proposed a dry type electrosensitive recording sheet. wherein an image is obtained by dispersing metal compounds capable of being electrically reduced into a free metal in an insulative resin. followed by reduction of the metal compounds into free metals through conduction of electric current. In this electrosensitivc recording sheet, however. most of the metal compounds of relatively high electric conductivity are colored. while less-colorcd metal compounds are of low electric conductivity. hence they require chemical and physical treatments for the electric current to be conducted therethrough. However. such treatments bring about coloration of the metal compounds with the consequent increase in density of the base color of the recording sheet to a considerable degree. Moreover. difficulty in electric conduction through the insulativc resin dispersion causes issuance of undesirable odors due to heat from the electric discharge at the time of recording. considerable degree of wear and tear in the stylus, and other defects.

Furthermore. Japanese Pat. No. 5476/[967 and No. l3239/l967 disclose a method wherein an electrically conductive thin layer is formed on a white or transparent substance such as silica. and so on by means of evaporative deposition, after which the substance is dispersed in a matrix for the electric conduction. However, even this method requires a considerable degree of skill and knack in the processes for such treatment.

As stated above. therefore, the conventional recording methods posed various problems in forming an image on the recording member in view of no effective means for the electric conduction having been developed in the wet type recording.

SUMMARY OF THE INVENTION It is therefore a main object of the present invention to provide image recording members having an improved recording layer in respect of its electric conduc tivity.

It is another object of the present invention to provide image forming members capable of forming an image thereof in substantially dry condition and being stable without regard to humidity in the surrounding atmosphere.

It is still another object of the present invention to provide image recording members which are capable of responding to even a slight change in the electric quan tity to be imparted thereto. of providing recorded im ages of high quality, and of providing excellent repro duction of the image with good tone.

It is a further object of the present invention to provide an improved recording method which is capable of responding to even a slight change in electrical quantity to be applied to the image recording member, of providing a recorded image of high quality, and of providing excellent reproduction of the image having good tone.

it is a still further object of the present invention to provide image recording members capable of responding to a high speed recording, and the electrically conductive recording method using such image recording members.

It is another object of the present invention to provide image recording member having a background of a high degree of whiteness and of excellent touch.

[I is still another object of the present invention to provide image recording members which are producible by a very simple procedure.

It is still other object of the present invention to provide image recording members which are highly stable in storage for a fairly long period of time.

It is still another object of the present invention to provide image recording members which are non-toxic and safe at the stages of production and use.

The characteristic features of the present invention to attain the abovementioned objects reside in that. in the image recording members having an active layer for recording which comprises. at least. an electrically conductive agent. an image forming agent. and a binding agent. the electrically conductive agent consists of a porous compound containing therein a polar substance. and that the required image is recorded on the image recording member by causing electric current to flow in the abovementioned active recording layer.

The foregoing objects as well as detailed construction and functions of the present invention will become more clearly understandable from the following description thereof. when read in conjunction with the accompanying drawings and several preferred examples to reduce the same into practice.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings. FIGS. 1. 2. and 3 are respectively schematic diagrams illustrating the structure of the image recording member. and the recording method using the same according to the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS To begin with, the image recording member and the electric discharge recording method using such image recording member in accordance with the present invention will be outlined hereinbelow with reference to FIGS. 1 to 3 inclusive ofthe accompanying drawings which diagramatically illustrate different embodiments of the image recording member.

The image recording member shown in FIG. I consists of a base layer 3 of any appropriate material, an electrically conductive. intermediate layer 2 placed on the base layer, and a top recording layer 1 provided on the intermediate layer. This image recording sheet is used to obtain an image thereon by the electric discharge recording method according to the present invcntion.

The top. recording layer l consists ofa porous compound (A) containing therein a polar substance. an image forming agent (B). and a binding agent to bind these two substances.

The image recording sheet as shown in FIG. 2 consists of the base layer 3. the electrically conductive. intermediate layer 2 placed on the base layer 3. another electrically conductive layer 5 which corresponds to the top. recording layer 1 of FIG. I as described above except for exclusion of the image forming agent (B) therefrom and which is placed on the intermediate layer 2. and an image forming layer 6 placed a top of the layer 5 and containing therein the image forming agent (B). In this case. the so-called recording layer as used in the previous embodiment of FIG. I designates the electrically conductive layer 5 and the image form ing layer 6 as combined.

Further. the image recording sheet as shown in FIG. 3 consists only of the base layer 3 and the recording layer 1. these being the same as those in the image recording sheet of FIG. 1.

Throughout these embodiments in FIGS. I. 2 and 3. the reference numeral 4 designates an electric power source. the numeral 7 denotes a stylus, and the numeral 8 represents a feedback electrode. The electrode 8 may be taken directly from the electrically conductive layer 2. or from the recording layer I or the image forming layer 6. The polarity oi'electricity to be impressed upon the stylus 7 may be either positive or negative I-). or an alternating current.

The porous substance (hereinafter simply referred to as compound tAl") which contains therein a polar substance to he used as the electrically conductive agent for the purpose of the present invention is understood to have to following physical properties. That is:

l the compound (A) possesses porcs" or "cavities" in its molecular structure. in which a loosely bound polar substance (as will be described in more detail at a later paragraph) can be held. And. even in this state of containing a sufficient amount of polar substance in these pores or cavities. the compound (A) does not exhibit stickincss as seen in the hygroscopic and efl'lorescent phenomena which is generally shown by sodium chloride and like salts. but it maintains an apparent dry state.

2. the compound (A) does not lose its crystal structure. even when the polar substance it contains is complctely removed under heat. reduced pressure. or any other expedient.

3. the compound (A) exhibits good electric conductivity on account of the polar substance and various kinds of ions. with which it may co-exist.

4. the compound (A) is capable ofexhibiting its electric conductivity by adsorption of a sufficient amount of water even if it is left in the natural atmosphere.

As mentioned in the preceding paragraphs. the compound (A) has very unique physical properties. The present invention has just noticed these physical properties of the compound (A). and. after strenuous and painstaking studies and experiments. has found out that the image recording material produced from a system. in which the compound (A) is dispersed in a binding agent can exhibit the characteristics of the compound in a substantially same degree as does the compound (A) per so.

The compounds (A) which are applicable for the purpose of the present invention are as follows.

1. Ion-Exchange Resin Synthetic resins which consist principally of porous high polymers containing therein ion-exchangeable acid groups or base groups fall under this category. Types of such ion-exchange resins are cationic ionexchange resin. anionic ion-exchange resin. and amphoteric ion-exchange resin.

The composition ofthe high polymer to be the principal constituent ofthe ionexchange resin maybe any of polystyrene amine type. phenol methylene sulfonic acid type. polystyrene sulfonic acid type. phenol formaldehyde polyaminc type. methacrylic acid type. and vinyl resins.

The acid groups may, for example. be sulfonic acid groups (-SOgOH), carboxylic acid groups COOH), and phenolic hydroxy groups OH). The base groups may. for example. be amino groups (-NH Lsubstituted aminogroups(NHR. NRR'). and quaternary ammonium salt groups N *RRR).

2. ElcctromExchange Resin High polymer compounds which perform the elec tron-exchange fall under this category. among which polyvinyl hydroquinone. hydroquinone formaldehyde resin. dioxyphenyl alanine polymers, etc. may be exemplified.

3. Hydrophilic cross linked copolymers consisting of ternary components A. B. and C. wherein the component A is 60 to 90% by weight of a hcterocyclic-N- vinyl monomer represented by N-vinyl lactam. the component B is 40 to lO'7r by weight ofa monomer selected from vinyl acetate and methylmethacrylate. and the component C is. for example. polyethylene glycol dimethacrylate. 0.5 to 127: by weight of which is added to the total quantity of the components A and B.

4. Porous Polyester Resin The polyester resins are represented by those which are produced by the undermentioned process steps.

a. providing an inner phase forming agent which is water or a liquid substantially consisting of water:

b. providing an outer phase forming agent which is a polymerizable organic liquid consisting of the following two components:

(compound a) a polyester consisting of a polycarboxylic acid and a polyhydric alcohol, and having in its molecules at least one functional group represented by COCH=CHCO-; and

(compound b) a low molecular weight. polymerizable liquid monomeric compound which is copolymerizable with the component a. and is capable of containing therein a low molecular weight. polymerizable nonliquid monomeric compound;

c. preparing an oil-water emulsion with water as the emulsifier in the presence of one. or two. or more kinds of inorganic metallic compounds of low solubility in water such as. for example. sulfides. hydroxides, and oxides of mercury. lead. bismuth, copper. cadmium. antimony. nickel. cobalt. iron. zinc. manganese. aluminum. and chromium; and

d. subjecting this oil-water emulsion to blockpolymerization in the presence of a polymerization catalyst and. depending on necessity. a polymerization accelerator to produce a porous synthetic resin. a part or whole of the inner phase forming agent being removed from the produced synthetic resin depending on necessity.

5. A substance having therein micro-pores. the substance being produced by pouring. in a flat sheet form. a uniformly mixed solution consisting principally of a condensed copolymer resin of dichlorodiphenylsulfone and bisphenol (hereinafter called simply Polysulfone." a trademark for a product of OCC). chloroform as a solvent. and alcohol having 1 to carbon atoms as a non-solvent. and then subjecting the flat sheet of the poured solution to volatilization and drying at a temperature which is below the softening point of the resin so as to form micro-pores in the resin sheet.

6. Silicic Acids and Silicates a. porous silicic acids represented by xH- .O.ySiO which is known as silica gel. silica acrogel.

b. silicates represented by xM O.ySiO and occurring in nature as sticky ores. examples of which are amorphous ones such as allophane. hisingerite. etc.. and crystalline phyllosilicatc such as montmorillonite group. pyrophylite group. talc group. mica group. kaolin group. ehlorite group. vermiculite. etc.

c. porous silica glass which is an intermediate product obtainable at the time of quartz glass production.

7. Aluminum Silicate Various sorts of condensed acids may be given. of which a typical one is natural zeolite. This is also called aluminum silicate to be represented by the following general formula: M (MW 0 Al. .O;, mSiO nH O (3 g m [0). where: M and M indicate respec tivcly divalent and monovalent metal ions. most of which are usually (11 and sometimes St Ba. and

K*. all being capable of being replaced with other cations. These zeolites have specific "cavities or pores in the three dimensional skeleton structure. and the above-mentioned replaceable cations are held in these pores together with water molecules. Besides water. other organic solvents can be absorbed in the cavities. and the solvents of high polarity can be selectively absorbed. There exist a great many kinds of synthetic zeolites which have substantially the same three-dimensional skeleton structure as that of natural zeolite. and which are not much different from natural zeolite in respect of the basic properties.

Furthermore. there are natural or synthetic compounds which have chemical compositions completely different from zeolite. in spite of the fact that they have the same basic properties as zeolite. i.e.. they have the cavities. and do not change their structures in absorption and desorption of water. Such compounds are called zeolite-like compounds. which are also useful for the purpose of the present invention.

Zeolites both natural and synthetic which are used in the present invention may be classified as follows.

(I Analcime Group:

Molecular sieve A" Molecular sieve X* Molecular sieve Y* Molecular sieve SK Molecular sieve R the same as Chahazite Molecular sieve S the same as Gmelinite Molecular sieve T* the same as Elionite NOTF; Synthetic zeolite manufactured by Union Carbide ('orp.. SA. (4) Natrolitc Group:

NOTE. ".S \l'l\hI:llL Yunlih: manufactured b l'nion Carbide Corp. LISA. to] Mordcnite (iroup:

Mordenite Nat AlShO lfiH o Dachiartlite (Na Ca MAI IS JIIOJ'h EH 0 Ferrierite N= l .-.Mg l A|..5si.... ,,0., lXlH O Zeolon" the same as Mordenite .\()T[;' "Manufactured by Norton (o (7| Zeolites of nun-determined structure:

-continued Bikitaite LiAISi O H JJ The above compounds are all applicable to the present invention.

(8) Zeolite-like compounds:

(8-l) Zeolite-like silicate not classified as zeolites. but which contain zeolitic water.

Cordierite Mg AL lAISi O InH O Milarite KCa AIBeQSi O IQSH O Osumilite lK.Na.Ca)l Mg.Fe l t ALI-e );|l Si.Al l.

Hydrated Nepheline Hydrated Nepheline (ancrinitc Buddingtonite (82) Other zeolite-like compounds:

(II Germanate MalHGe.(UeO ];.0.|.4H:O.

where. M is a metal ion.

(lll Phosphate.

Arsenatc. FCAfiO ZH O Scorodite Pharmacosidc Kl Fe tOH IA AsO l;.l.o-7H llllJ Water-containing metal oxide Psilomelane lBa.H:0) .Mn,-.O (IV) Three structure complex Prussian blue ai Fel CN M1 l 2H4).

The above-listed compounds are all applicable to the present invention. In particular. however. those compounds having large cavity volume. or porosity and a high content of the polar compound. hence exhibiting good electric conductivity, are preferred.

8. Basic Aluminum and Magnesium Carbonates The compounds are represented by the following general formula:

(where: .t. v. and z are respectively integers which satisfy the relationships of and u is zero or an integer which satisfies the relation ship of example. carhoxylic acid salts ol compounds reprcsented by RlOlCH ,..(O()H.B. R()(OtLH- .COOH.B (where B is an organic amine and so on. trietltanolaminc salt of ectylsulfonic acid. dicthanolamine salt of alkyl sull'onic acid. naphthalene sulfonate. sodium salt of oleyl henzimidazole sulfonic acid. and so on. phosphoric acid derivatives such as. for example. various sorts of salts from phosphonic acid. phosphinic acid. phosphite esters. phosphoric acid esters. and so on. alkylaminc salts such as. for example. l'octadccyl- S-mcthyl-higuanidc hydrochloride. dibutyl phosphoric acid-tetraethylenc pentamine salt. and so forth. salts of cyclic amines such as. for example. heptadecyl imidazoline. dimethyl-aminoacctoguanamine. and so forth. salts of amideamines from high class fatty acids and low class polyamincs such as. for example. N-monoacetyl ethylcncdiamine. etc. salts of estcramines such as. for example. ester amines of stearic acid and triethanolamine. esters of stearic acid and w.w'-diaminopropyl octadecyl ethylene glycol ether. and so on. quaternary ammonium salts such as. for example. alkyl dimethyl henzylammonium salt. alkyl trimethyl ammonium. and so on. and salts such as. for example. guanidine salt. alkyl alanine. alkyl aminosulfonic acid. etc. obtained by reacting maleic anhydride with alkyl amine.

For the polar substance to be impregnated in the porous compound (A). various expedients such as heating. application of a reduced pressure. etc. can be adapted depending on the situation. However. sufficient impregnation can be attained by simply leaving the porous compound (A) and the polar substance under the natural condition. in case the latter is water. Also. where the required amount of the electric current conduction cannot be obtained for the image recording with impregnation of the water alone as the polar sub stance. any of the aforc-mcntioned organic or inorganic electrolytes may be used together for more effective image recording. The ratio of impregnation of the polar substance into the porous compound (A) in accordance with the present invention usually ranges from about [0 to 75'7r by weight. or. more preferably. approximately 30 to 70% by weight.

The image forming agent as used herein are those ca pable of forming images in response to changes of energy by application of electricity. There can be employed any known compound such as, for example. oxidation type color formers, reduction type color formers. pH indicators. heat-sensitive color formers.

and the like.

As the reduction type color former. there can be 9 carboxyphenyl)4-dicthyl-aminophenylmethane. and so on: leuco compounds of xanthene such as 3.6- dil dimethylamino) xanthene; leuco compounds of acridine dye such as 3.(i-di-amino-2.7-dimethy]9- phcnylacridine. 3.6-di(dimethylamino) acridine. and so forth; leuco compounds of azine dyes such as 2- methyl-3-amino-7-dimethylamino-5.l0- dihydrophenazine. 3.7-diamino-5-phenyl5.l0- dihydrophenazine and so on; leuco compounds of oxazine dyes such as 3.7-di(dimethylamino) phenoxazine and so on; and leuco compounds of thiazines such as 3.7-ditdimethylamino) phenothiazine and the like.

Furthermore. there can be listed reductants ofindigo and indigoid dye. leucoferrocyanine. and leuco base vat colors of paraquinones such as benzoquinone dyes. naphthoquinone dyes. anthraquinoncs. and so on; aromatic amino compounds such as p-aminodiphenylamino. diphenylbenzidine. oxidation bases which produce oxidation dyes such as phenols like 4- methoxyd-naphthol. l.5-dihydroxynaphthalene. and so forth; and reductants of sulfide dyes such as 2- mercapto-3-hydroxy-7-dimethylaminophenothiazine, and so on.

As the reduction type color former. there may be given tetrazolium salts such as triphenyltetrazolium chloride. ditetrazolium chloride and so on; long chain aliphatic acid ion salts such as ferric stearate. and so on; organic acid noble metal salts such as silver behenate. silver stearate. and so on; oxalic acid metal salts such as silver oxalate. nickel oxalate and so on metal carbonates such as manganese carbonate. cobaltous carbonate. and so on; metal chlorides such as nickel chloride. copper chloride. and so on: and heterocyelic quaternary ammonium salts capable of forming anhydrous salts by reduction such as l-methyl-2.2'.4'-dinitrobenzylpyridium p-toluene sulfonate. l-methyl-4- chloroquinaldium sulfate. and so on; and metal com pounds such as molybdenum trioxide. thorium oxide. cerium oxide. phosphotungstic acid. phosphomolybdenum acid. ammonium phosphomolybdenate. and so on.

As the heat-sensitive color former. there may be given single heat sensitizers such as indole derivatives. pyrrolone derivatives. and substituted amino dithioformic acid heavy metal salts; and two-component heat-sensitizers such as long chain aliphatic acid ion salts such as ferric stearate. phenols such as tannic acid. ammonium salicylate. organic heavy metal salts such as nickel acetate and the like. alkali earth metal sulfides ororganic chelates such as diphenyl carbazone, organic acid noble metal salts such as silver bchcnate. aromatic organic reductants such as hydroquinone. protocatechuic acid. higher aliphatic heavy metal salts such as ferric stearate. disubstituted dithiocarbamine acid zinc derivatives such as zinc dihutylthiocarbamate. and so on. In addition. there may be given two-component based color forming heat sensitive agents such as combinations of members selected from color formable lactone compounds such as crystal violet lactone, 3- dimethyl-amino-(i-methoxyfluorene; color formable lactam compounds such as rhodamine B lactam; leuco compounds of dyes such as leuco crystal violet. leuco malachite green; and spiropyran compounds such as l. 3. 3-trimcthylindolyno-8'-methoxybenzopyryl spiran. l-amyl-3. 3-dimcthylindolyno-8'-ethoxybenzopyrylspiran and one member selected from acidic compounds such as bisphenol A.u-naphthol. and palmitic acid.

There has heretofore been known to include iodine compounds such as potassium iodide in a recording member. the compound of which is electrically excited to exhibit color due to the starch-iodine reaction. whereby a visible image can be obtained. Also. there has been known a method. in which iodine compounds. and amines or their leuco derivatives are included in a recording layer. and. upon liberation of iodine by electrical means. the amine or its derivative is reacted with the liberated iodine. whereby an image is recorded on the recording member. These known methods are also applicable to the present invention.

Examples of the iodine compounds to be used in these methods are: zinc iodide. aluminum iodide. anti mony iodide. ammonium iodide. indium iodide. uranyl iodide. cadmium iodide. potassium iodide. calcium iodide. silver iodide. cobalt iodide. zirconium iodide. mercury iodide. tin iodide. strontium iodide. cesium iodide, cerium iodide. thallium iodide. tungsten iodide. ferric iodide. copper iodide. thorium iodide. sodium io dide. nickel iodide. platinum iodide. barium iodide. beryllium iodide. magnesium iodide. manganese io dide. and lithium iodide. Also. oxides of iodine such as iodine pentoxide. iodine tetraoxide. and so on. as well as iodic acid and iodic acid ammonium can be used. Of these various iodine compounds. those having strong ionic coupling such as iodides of alkali metals or alkaline earth metals are particularly preferable.

The compounds which react with iodine liberated from the abovementioned iodine compounds to form an image are: starch. starch ethers. amylopectin. polyvinyl alcohol. polyvinyl formal having a high OH value. etc.. Besides these. there may be given piperine. cellulose treatcd with zinc chloride. praseodymium acetate. lanthanum propionate. nylon. and so on. Also. aromatic amines such as tetramethyl-p-phenylenediamine. N. N-dimcthyl-p-phenylenediamine. tetramethyl diaminodiphenyl methane. etc. can be used. Besides these amines. there are further used color bases. and leuco compounds such as tris(p-dimethyl aminophenyl) methane. 3. 4-benzo-6- dimethylaminofluorene. bis(p-diethylaminophenyl) phenylmethoxy methane. and so on.

There is still another method of forming an image by use of the below-listed compounds as the image forming agent. wherein a recording layer containing any of these image forming elements is electrified to differentiate its property, either hydrophilic or hydrophobic. after which it is used as a master plate for offset printing. The examples of the abovementioned image forming element are: tetrazolium salts. ditetrazolium salts. triazolium salts. or petroleum waxes such as mictocrystalline wax (containing isoparaffin of 32 to carbon atoms as the principal constituent). paraffin wax of a melting point of 37.8 to 645C (containing n-paraffin of 16 to 40 carbon atoms as the principal constituent). and petrolatum wax of a melting point of 38 to 60C.

Besides the above. it is possible that a part or all of the ions (A) such as, for example. sodium ion. potassium ion. etc. which the abovementioned porous compound (A) contains may be exchanged with other ions (8') such as. for example. silver ion. gold ion. copper ion. ammonium ion. nickel ion. cobalt ion. iodine ion. iron ion. magnesium ion. and so forth which are necessary for forming an image thereby to produce a porous compound (B) which is directly used as the image forming agent.

The binders as used herein include gelatin. natural high polymers such as starch; cellulose derivatives such as cellulose nitrate. carboxymethyl cellulose and so on; semisynthctic polymers such as natural rubber plasticizer. e.g.. chlorinated rubber. cyclized rubber. and so on; polymerization type synthetic polymers such as polyisobutylene. polystyrene. tei'pene resin. polyacrylic acid. polyacrylate. polymethacrylate. polyacrylonitrile. polyacrylamide. polyvinyl acetate. polyvinyl alcohol. polyvinyl, pyrrolidone. polyacetal. polyvinyl chloride, polyvinyl pyridine. polyvinyl carbazole. polybutadienc. butadienc-styrenc copolymer. butyl rubber. polyoxy methylene. polyethylene imine. polyethylene imine hydrochloride. poly(2-acryloxyethyl dimethylsulfonium chloride). and so forth; condensation-polymcrization type polymers such as phenol resin. amino resin. tolu ene rcsin. alkyd resin. unsaturated polyester resin. allyl resin. polycarbonate. polyamide resin. polyether resin. silicone resin. furan resin. thiokol rubber. and so on; and addition-polymerization type polymers such as polyurethane, polyurea. epoxy resin. and so on.

The recording members according to the present invention are produced in the following manner.

The porous compound containing therein the polar substance. image forming agent. and binder (if necessary. together with pigment. color controlling agent and other additives) are uniformly dispersed. and the dispersion liquid is applied on any suitable substrate by coating. dipping. or other expedients to form a record ing layer. The quantity of the porous compound con' taining the polar substance for use in the present inven tion generally ranges from to 98% by weight based on the total weight of the recording layer. and preferably from to 95% by weight. A more preferable range thereof is from to by weight, although the present invention is not confined to this specific range.

For the substrate. there can be used paper. resin film. conductive material such as metal. conductive paper treated with thin metal film. conductive paper having thereon vapor-deposited metal. conductive paper coated with metal powder. conductive paper treated with carbon. and so forth.

PREFERRED EXAMPLES In order to enable those persons skilled in the art to reduce the present invention into practice. the following preferred examples are presented. it should. however. be noted that these examples are illustrative g only. and they do not intend to limit the scope of the present invention as set forth in the appended claims.

EXAMPLE 1 Component Part by Weight Porous Compound IA) of a class as listed in the following Table l llltl Rulile type titanium oxide 2U Poly inylbutyral (pd LSUIH 3t) l.lliantil Illll A mixture of the above-mentioned components was kneaded for seven full days and nights in a ball mill.

after which 5 parts by weight of leuco malachite green as the image forming agent was added to this kneaded mixture and further mixed sufficiently. This kneaded mixture was then applied onto an aluminum foil to a film thickness of approximately 8 microns by use of a coating rod. Subsequently. the thus coated aluminum foil was subjected to heat-treatment in an oven maintained at C for 5 minutes. whereby a recording layer is produced.

Then. a tungsten stylus was connected to a positive and the aluminum foil to a negative 1-) and a DC. voltage of approximately volts was impressed thereacross. and the stylus was caused to scan on the above-mentioned recording layer at a speed of tin/sec. The results are as shown in the following Table l.

NUTFS. i "I Trademarked ion-c\cbange resins ol' Robni a Haa (1).

t lConsishng ol' 7 parts by wciglit oi' Nwin lp rrolidonc. .1 Paris by weight ol methylmeihacrylatc. and l part by weight of polyethylene glycol diinctliacrylalc t i ('onsisliiig of l part by weight of trinicllnlolpropaiie lrit'uinaratc. and 1 art by eight of tlt\ll\}l ben/cne i i MgAL-IOH 1.. ('t) 2H i I Tilaiiium oxide ot Sakai Kagziku K K. Not porous, l sed tor comparison purpose only [\plananons oi \)1t\httl lor Rccordabdii \crt (iootl (1 (mod .3 Recordable. though not good X Poor EXAMPLE 2 Kaolinite. polyvinyl hydroquinonc. porous polyester. basic aluminum/magnesium carbonate. which were evaluated as having the recordability grade of A in Example l. above. were subjected to drying under a reduced pressure. after which each of the polar substances listcd in Table 2 below was adsorbed to each of these compounds (A).

The recording layer was then formed by using each of these compounds containing therein the respective polar substances in exactly the same manner as mentioned in Example I. and the produced recording layer was subjected to the recording in the same way as done in Example 1 above. The evaluations of recordability of the recording layer containing each of the polar substances are as follows:

Table 2 linpro\ cnicnt in Polar Substance Rccordability (jlyccrinc Polyethylene glycol Lithium chloride Sodium chloride Monoetlianol amine but rate Sodium N-steroyl sarcostriate Table 2 -Continued lmprolemcllt in Rccordnbilily Polar Substance EXAMPLE 4 The recording layers were produced by the use olthc molecular Sieve Sk-4(l in groups A and B as in Example Alkyllfifllclhyl G) 5 3 above. and they were subjected to the recording tests by varying the scanning speeds of the stylus. The NlZJTlu: lhe criterion of lhe elillllllleil imprmemenl in reeordllblllly is its lnllim composition of thfl recording paper and thC operating @\er) remarkable imprm m min r u rullbllm r u nil din inn rl \ll conditions for the recording were exactly the Same as 'L' L' U 0. Clilhl e wllh raillm h l, g those ln Example 3 above. The results of the recording Remarkable imPI'KNCIHLIH in record-ability recognized in comparison with H) are as Shown in Table 4 below. l-xiimple l,

A Slight imprmement in remlrduhilil) recognized in comparison with |.\lllll u c 4 pll L Rccordilbllity Scanning Speed of Compound compound From the above Table 2. it ls found that presence ol smug (tn/NJ [M (Bl the polar substance other than water. particularly varl- 7 ous sorts of electrolytes, serves to improve in the :1 o recordability. 2.0 A (9 3.0 A 0 EXAMPLE 3 A O To a mixture of 2g of clltetrazollum chlorlde. 10g of polyvrnylbutyral (polymerization degree of 1.500). 5g The criterion for the evaluation is the same as in of mole type tltanlum oxide, and 150g of ethanol, there Examp|e 3 From the above experiments, i h b s added 2 of vauous kluds of Porous compounds found that high speed recording is possible due to the as listed in Table 3 below, and the batch was kneaded presence f h l l t for 2 full days and nights.

The compounds in group A of the Table are those po- EXAMPLE 5 runs compounds containing only zeolitic water which In this Example 5. the recording papers were prothe compounds contain primarily, while the comduced by using an electrically conductive agent obpounds in group B of the Table are those having sodium tained by the adsorption to the porous compounds of chloride (NaCl) contained in the so-called cavitics" a 10% q eo s solution f v ri s ele tr lytes s or porcs they have. shown in the following Table 5.

The dispersed liquid after the kneading was applied T rccorqmg layers wcre sublcclcd m the on) an muminum laminate paper w a film thickness of me conductive recording. and the results of recording approximately l0 microns by means ofa coating rod, f compaljed among them, thfi compared results and then dried for 5 minutes at a temperature of 100C. bcmg Show m Table 5 bcmw' After the drying the recording paper thus produced As the porous compound. there was used molecular was subjected to recording by electric conduction in 2'31 (prudufcg 'P such a way that a tungsten stylus was connected to a 'mpregna 6 W1 a o aquicous so u Ion O 40 the electrolyte shown in the following Table 5, the negative. while the aluminum laminate paper to a poslelectrolyte being adsorbed to the compound in a tlve, across which a DC. voltage of approximately I volts was a lied and the st lus was caused to summer" quanmy' h g, y d f70 I As the binding agent. polyvinylbutyral was used at a Scan on l ti h a? at a Spee :1 weight ratio of5 to 1. Also. as the image forming agent. Ttlle rfesu ts i t e recur mg are as 5 Own m t e 45 there was used triphcnyl tetrazolium chloride at a re lowmg Tab e weight ratio of H20 with respect to the total weight of T bl 3 the porous compound.

Recordabilily Table 5 Compounds A so Electrolyte lmprovclrle n t ln Molecular Sicve'SKAll Rcclmhlhlhll s l lists filial? s s w Lithium chloride cddellitc O s dd Ciismondllc A 0 9 lrlcthanclumlne cctyl A Chabazllc A O sull'onalc f l A O Dimcthylaminoacetoguanaminc A Cllnoptllotite A O sull'atc Mm'dfmilc 3 0 Potassium olcale O Sodalltc A l) Alkylbcnzcne calcium 0 Anulcilc A sull'oltaltc Psilomelanc A Ltlurylaminc hydrochloride A Concrinitc A Sodium stealryluminopropionatc 0 hold Produced h lnlon (iirbldc Corp iaxplunntlnns of symbols [or "Reulrdaihillly" cr) Good (1 Good A Ret'nrdlihlc. though not good From the above results. it has been found that the recordubility improves by the presence of the electrolytes in the compounds.

Note The criterion of the muluulcd lmpnnement ln rccurtliihillty is as follows er remarkable im rovcnlcnt In recorduhillt recognl/ed. l) Remarkable improvement I rccordublllly rceogni/ed Slight improvement in rcclirdil ility recugnl/ed.

EXAMPLE 6 The scanning of the recording layer by the stylus at a rate of 0.7m/scc. as in Example 4 above was done under the following conditions of relative humidity. and the record-ability of the layer was examined. The composition of the recording layer and the other conlwmd'cnl Pans by Weigh! ditions are the same as in Example 4, and the results Mtmltlmrillcllllt loo are as shown in Table 6 below. 5 Pollavtijnyfilgxtfiral 2 l) T bh 6 Sodium iodide l.tl

Additive lsee lable K Relaliw Humidity RCCOYdLlhIllH F H) (l Compound A (ompound l3 lllhimll n so G) It) 40 t (9 The thus prepared dispersion liquid was applied into Ill (J y I H 5 A 0 an aluminum laminate paper to a thickness ol approximately 8 microns. and dried to obtain the recording pa- Note: The symbols for recordability have the same meanings as those in Example p s The stylus was caused to scan on this recording paper F h b v for image recording under the same conditions as in f Ovc results) It found that. 'm Example I. the results of which are shown in Table 8 cordability in the recording at low humidity could be bcluw obtained due to the presence of the electrolyte. V

Table 8 EXAMPLE 7 Additive Compound Reeorded olor Various kinds of recording papers were prepared in Starch Mgmmmm rm Ed the same manner as described in Example I with the Amylnpeetin purple exception that various image forming agents were used Ljtlmhfimum t l I f 1S Piperine dark brown in place of leueomalachite green. The recording papers Ccuuhm. "Mud Mm were subjected to recording by application of electriclint vhlvridle h da k r n g i l'etramethy pump en ene ity, the results of which are as shown in Table 7 below. dimuinc Hue N.N'-dimethyl-p;iraplten)lent:

Table 7 image Forming Agent Reeord- Recorded Polarity ability Color of stylus Leueo auramine 0 yellow 3.6-dildimethylamino] xanthene red 3.7-diamino5.lfi-dihydrophenaziiie red 3.7-ditdimethylamino)pheriothiazine blue 4-methoxyl -naphthol blue Bisl p-dimethylaminophcnyl lmethane 0 blue Leueo crystal violet blue-purple Hist 3-methyl-A-hydroxyicarhoxyphenyll. o-diehlorophenyl methane red-purple 3.(i-diamino-2.7-dimethyl J-phenylacridan 0 red 3.7-ditdiethylamino)phenoxazine Q) blue Indigo white dard blue p-aminodiphenyl amine rk blue tmethyl-2.2'.4-dinitrohenzyl pyridiniump-toluene sulfonate purple-blue Dibromo phenol sulfophthalein red Phenolphthalein 0 red Triphenyl tetrazolium chloride red Ditetrazolium chloride dark blue Nickel oxalate 0 gray-brown Cobaltous carbonate 0 gm -hrown Silver hehenate O gray-brown Phospho-tungstie acid gray-black Niekel hypophosphite 0 gray-brown Zine oxide gray-black diaminc blue 'l'etramethyl-diaminodiphenyl EXAMPLE 8 methane blue 'l'rist p-dimethylaminophenyll Instead of a l in a direct current of ositive or P P y g p 3.4-benzo-o-dimethylamino negative polarity to the stylus as in Example 7 above. flmmm red an alternating current of approximately 150 volts was Bisl P dlUll1 llltt1tl'ltlfilttlt)ll W phenylmethoxymel ane blue applied thereto to carry out the recording in the same N additive wry gm manner as in the preceding Example. As a result. a yellow good image was obtained without a change in the color tOl'lC.

EXAMPLE 9 EXAMPLE It) A mixture of the following ingredients was kneaded in a ball mill for 2 full days and nights to prepare a dispersion liquid.

A mixture oi the following ingredients was kneaded iii a ball mill for two full days and nights to prepare a dispersion liquid.

across which a current of approximately 150 volts was impressed. while the stylus was being scanned on the Pans by weight recording plate. With the electric conduction. the con- Monlntortllonite too ducted portion became transparent. and at the same P T -l F 5 time. became water-repellent. Sodium lOLltLlL 1.0 rim-mm mu The recording plate. on which an image was thus recorded. was then subjected to an offset printing by means of an offset proof printer. from which a good The thus prepared dispersion liquid was applied onto print Of an image corresponding to the electrically an lumin m l min t paper t a thi k ufupproxiconductive image recording could be obtained. The mately 8 microns. d d i d to b i h di serviceable life of this recorded plate for the offset per I printing was approximately 4.000 to l0.000 sheets of On the other hand. another dispersion liquid was pre- P pared f a mixture f h f ll i iflgrcdicntg d H ln place of the abovententioned microerystalline the it was applied onto an impregnation paper, which wax. paraffin wax was used for preparing the dispersion was dried and made into the r di paper I] liquid in the same way as mentioned in the foregoing.

The application of the dispersion liquid on the recording plate. the electrically conductive recording on the Ingredient n Weight 70 coated recording plate. and the subsequent offset printqq uiwhfii H) ing were also carried out in exactly the same manner as ea. l.00ll) in the proceeding. The results obtained were substan- Addltlve (see Table 9 below) M tially the same as above. Water l0.0

EXAMPLE i2 A mixture of the following ingredients was kneaded When the abovementioned recording paper l was in a ball mill for full 2 days and nights to produce a dissubjected to the electrically conductive recording persion liquid. under the same conditions as in Example 1. a light yellow portion appeared on the image recording paper. w Subsequently, the recording papers I and II were supermgmlicm "Y posed and caused to pass through a pair of heated rolls 5.ph y| 2 3.hi maintained at 140C for 5 seconds. whereupon an diph'nyllwmtlium "8 chloride image of a color as shown in Table 9 below was ob- Fuujmw [WC symhmc tained on the image recording paper ll at a position iklgllcl llllntilflclltlrzit?bk w corresponding to the lIght yellow portion on the reg l' 'z nr :i cording paper I. Polyvinylbutyral Tublg 9 tEpgllynrnlcnzatton degree L500) Additive Compound Recorded Color 40 l f f 0 The resulting dispersion liquid was applied onto an Lunihuzum pmpmnuw K l: hmwn aluminum plate of about 50 microns thickness by P p dark brown means of a coating rod to a film thickness of about 55: 1a pmphcnyicnc blue [0 microns, and dried under natural conditions. There- N y -p p y after, the recording plate was subjected to electrically a p i conductive recording by connecting a tungsten stylus methane blue to the negative, and the aluminum plate to the positive, across which a current of about 150 volts was imrnelhane purple No additive light yclluw pressed, while the stylus was caused to scan on the recording plate at a scanning speed of 50 cm/sec. As the result of this electric conduction, the conducted part assumed areddish-purple color, and, at the same EXAMPLE 1 1 time became water-repellent.

lOg of microcrystalline wax was added to a mixture The recording plate. on which an image was thus reconsisting of 30g of Amberlite IRA-40] (an ioncorded. was then subjected to an offset printing by exchange resin of Rohm & Haas Co. l0g of rutile type means of an offset printer, from which a good print of titanium oxide. 10g of polyvinylbutyral (polymerizaan image corresponding to the electrically conductive tion degree of 1,500). and 150g of ethanol. and the image recording could be obtained.The scrviceablelife whole batch was kneaded for full 2 days and nights in a of this recorded plate for offset printing was approxiball mill to produce a dispersion liquid. mately 3.000 to 5.000 sheets of print.

The dispersion liquid thus prepared was applied onto In place of the abovementioned 5-phcnyl-2.3-bis(pan aluminum plate of approximately 50 microns thickdiphenyl)tetrazolium chloride, various image forming ness by means of a coating rod to a coating thickness agents as listed in the following Table 10 were used for of approximately 10 microns. and dried under the natpreparing the dispersion liquid in the same way as menural condition to obtain a recording plate. Thereafter. the recording plate was subjected to the electrically conductive recording by connecting the tungsten stylus to the negative. and the aluminum plate to the positive.

tioned in the foregoing. The application of the dispersion liquid on the recording plate. electrically conductive recording on the coated recording plate. and the subsequent offset printing were also carried out in ex 19 actly the same manner as in the preeeeding. The results obtained are as shown in Table 10 below.

Table l() Image Forming Agent Printability 2.5-diphenyl-3-t4-styryl-phenylI O tetra/olium chloride 3.3'-l4.4'-biphenylenci-bis-I2.5- diphcnyltctrazolium chloride] 3.3'-dianisole biS[-l.4'-l3.5- diphcnyl)tetramlium chloride] m Ll N fiH (ll l N-N N C ll (22 o l @NO 2.2,5,5'-tetra p-nitrophcnyl- 3.3-t3.3'-dimcthoxy-4.4- biphenylenel-ditetrazolium chloride 3.3'-dimethoxy-4.4'-diphenylene- 3'.3"-bisl Z-phenyl-S-t Z-hydroxyphenyl) tctra/olium acetic acid salt 0 2.5-drphenyl-3-l4-nitrophenyl) tctra/olium fluoroboratc 0 Note. \cr) good 0 (loud EXAMPLE 13 As the porous compound (A), molecular sieve l3X (product of Union Carbide Corporation, USA. Amberlite [R420 (Rohm & Haas Co. U.S.A.). and bentonite (clay mineral of the montmorillonite group) were selected, and each otthcm was subjected to an exchange reaction in an aqueous solution to a sufficient degree with various cations (B') which contribute to the image formation, i.e., silver ion, copper ion, nickel ion. cobalt ion, and zinc ion, thereby producing various compounds (B After drying the compounds (B) in a vacuum, 50g of each compound was added to a mixture consisting of l5g of polyvinyl butyral (copolymerization degree of 1,500). lOg oftitanium oxide. and 100g ofethanol. and the whole batch was kneaded in a ball mill for full 2 days and nights to prepare a dispersion liquid.

The thus obtained dispersion liquid was then applied onto an electrically conductive carbon paper by means of a coating rod, to a coating thickness of microns,

and dried for 2 minutes at a temperature of C. whereby conductive recording paper was obtained.

Thereafter. the recording paper was subjected to the electrically conductive recording by connecting a tungsten stylus to the negative and the conductive carbon paper to the positive. across which a direct current of about 200 volts was applied. while the stylus was being caused to scan on the recording paper at a speed of SOcm/sec. The results are as shown in Table l 1 below.

into the dispersion liquid of Example [3. 2g of each of the electrolytic color formers as listed in Table I2 was uniformly dispersed, and the image recording was carried out in the same manner as in Example I. As a result, images of two color were obtained due to a conversion of the polarity of the stylus from positive to negative, or vice versa. For the porous compound (B), the silver ion exchange molecular sieve 13X was.

used. The results are as shown in Table 12 below.

Table l2 Electrolytic Color Recorded Color Recorded Former lstylus in posit- Colorlstvlus ive polarity) in negative polarity] leuco auramine yellow greyish black 3.6-dit diniethylaniino) santhcuc rcd greyish black 3.Tdiamino-S-phcnyl-i lli-dihydrophcna/inc red greyish black Leuco malachite green green grcyish black 4-methoxylnaphthol blue greyish black We claim:

1. In an electrical recording member provided with a recording layer containing an image-forming agent, an electrically-conductive agent and a binder therefor. the improvement comprising said electricallyconductivc agent comprising at least a porous compound contain ing therein a polar substance, wherein an image is formed on said recording layer by the application thereto of electrical current.

2. The electrical recording member according to claim 1. wherein said recording layer is a single layer comprising said image-forming agent. electrically-- conductive agent and binder.

3. The electrical recording member according to claim 1. wherein said recording layer comprises an electrically-conductive layer containing said electrically-conductivc agent and an image-forming layer containing said image-forming agent.

4. The electrical recording member according to claim I. wherein said image-forming agent comprises a porous compound containing therein a polar substance.

5. The electrical recording member according to claim I, wherein said porous compound is at least one member selected from the group consisting of ionexehange resins. electron-exchange resins, hydrophilic cross-linked polymers. porous polyester resins. and microporous bodies of condensed copolymcr resins of dichlorodiphenylsulfone and bisphenol. and wherein said polar substance is at least one member selected from the group consisting of polar solvents, inorganic electrolytes. and organic electrolytes.

6. The electrical recording member according to claim I, wherein said porous comppound is at least one member selected from the group consisting of silicic acid. silicates, aluminosilicates and basic aluminum magnesium carbonates. and wherein said polar substance is at least one member selected from the group consisting of polar solvents. inorganic electrolytes and organic electrolytes.

7. The electrical recording member according to claim I, wherein the content of said electricallyconductive agent in said recording layer ranges from 30 to 90% by weight based on the total weight of said rccording layer.

8. The electrical recording member according to claim 5, wherein said ion-exchange resin is a porous high polymer selected from the group consisting of polystyrene amine. phenol methylene sulfonic acid. polystyrene sulfonic acid. phenol formaldehyde polyamine. mcthacrylic acid and vinyl polymers containing an ionexchangeable acid or base group.

9. The electrical recording member according to claim 5. wherein said electron-exchange resin is a porous polymer selected from the group consisting of polyvinyl hydroquinonc. hydroquinone-formaldehyde resins and dioxyphenyl alanine polymers.

]0. The electrical recording member according to claim 5. wherein said hydrophilic cross-linkd polymer is a porous ternary copolymer of (a) 60 to 9071 by weight. based on the weight of the copolymer. of a hcterocyclic-Nwinyl monomer; (b) from 40 to by weight. based on the weight of the copolymer. of vinyl acetate or methyl methacrylate; and (c) from 0.5 to l2'7r by weight. based on the total weight of (a) and (b), of polyethylene glycol dimethacrylate.

I]. The electrical recording member according to claim 5, wherein said porous polyester resin is a resin produced by a process which comprises:

a. preparing an oil-in-water emulsion of a polymerizablc organic liquid consisting of t l a polyester of a polycarboxylic acid and a polyhydric alcohol and having at least one functional group of the formula -COCH CHCO. and (2) a low molecular weight. polymcrizablc monomer copolymerimble with fl) and capable of containing therein a low molecular weight. polymerizablc non-liquid mono- 22 nier: in the presence of at least one inorganic metal compound of low solubility in water: and

b. subjecting said emulsion to block-polymerization.

12. The electrical recording member according to claim 5. wherein said microporous body is produced by a process which comprises:

a. forming a flat sheet of a uniformly-i'nixed solution consisting essentially of a condensed copolymcr resin of dichlorodiphenylsulfone and bisphenol. chloroform and an alcohol having l to 5 carbon atoms; and

b. subjecting the resulting flat sheet to volatilization and drying at a temperature below the softening point of the resin.

13. The electrical recording member according to claim 5, wherein said polar solvent is selected from the group consisting of water. an alcohol. ammonia and dimethylformaldchyde; wherein said inorganic electrolyte is selected from the group consisting of the hydroxides. chlorides. iodides and bromides of alkali metals and alkaline earth metals; and wherein said organic electrolyte is selected from the group consisting of sulfuric acid derivatives, phosphoric acid derivatives. alkylamine salts. cyclic amine salts. amideamine salts. esteramine salts. quaternary ammonium salts and salts obtained by reacting maleic anhydride with an alkylamine.

14. The electrical recording member according to claim 6. wherein said silicate is a naturally-occurring amorphous or crystalline silicate.

15. The electrical recording member according to claim 6, wherein said aluminosilicate is represented by the formula:

M. (M*) O A1 0 mSiO nH O wherein M represents a divalent or monovalent metal ion, m is from 3 to 10 and n is a positive number.

16. The electrical recording member according to claim 14, wherein said aluminosilicatc is a natural or synthetic zeolite.

17. The electrical recording member according to claim 6. wherein said basic aluminum magnesium carbonate is represented by the formula:

wherein .r. y and z are integers which satisfy the relationships and a is zero or an integer which satisfies the relationship 18. The electrical recording member according to claim 6. wherein said polar solvent is selected from the group consisting of water. an alcohol. ammonia and dimcthyliormaldehyde; wherein said inorganic electrolyte is selected from the group consisting of the hydroxides. chlorides. iodides and bromides of alkali metals and alkaline earth metals; and wherein said organic electrolyte is selected from the group consisting of sul- 23 furic acid derivatives, phosphoric acid derivatives. alkylamine salts. cyclic amine salts. amideamine salts, esteramine salts. quaternary ammonium salts and salts obtained by reacting maleic anhydride with an alkylamine.

[9. The electrical recording member according to claim 1. comprising said recording layer on a base composed of an electrically-conductive material or an electrically-insulating material having an electricallyconductive surface.

20. The electrical recording member of claim I. wherein said porous compound has said polar substance impregnated therein in an amount of from ID to 75% by weight.

2]. The electrical recording member of claim I. wherein said image'fo'rming agent is a material capable of forming an image in response to the application of electrical current thereto. and is selected from the group consisting of an oxidatintype color former. a reduction type color former. a pH indicator and a heatsensitive color former.

22. The electrical recording member according to claim I, wherein said recording layer consists essentially of an image-forming agent. said electricallyconductive agent and a binder therefor.

23. A process for recording an image on an electrical recording member which comprises applying electrical current to a recording layer thereof. thereby forming the image on the recording layer which comprises an image-forming agent. an electrically-conductive agent 24 composed of a porous compound containing therein a polar substance and a binder therefor.

24. The process for recording an image according to claim 22, wherein said porous compound is at least one member selected from the group consisting of ionexchange resins, electron-exchange resins. hydrophilic cross-linked polymers. porous polyester resins. and mi croporous bodies of condensed copolymer resins of di chlorodiphenylsullone and bisphenol. and wherein said polar substance is at least one member selected from the group consisting of polar solvents. inorganic electrolytes. and organic electrolytes.

25. The process for recording an image according to claim 23. wherein said porous compound is at least one member selected from the group consisting of silicic acids. silicates, aluminosilicates. and basic aluminum magnesium carbonates. and wherein said polar substance is at least one member selected from the group consisting of polar solvents. inorganic electrolytes. and organic electrolytes.

26. The process for recording an image according to claim 23. wherein said electrical current is applied to said recording layer through a stylus.

27. The process for recording an image according to claim 23, wherein said electrical recording member comprises said recording layer on a base composed of an electrically-conduetive material or an electricallyinsulating material having an electrically-conductive surface.

UNITED sm'l'ics IA'Il-IN'I (mum-1 CERTIFICATE 0 1? CORRECTION Patent No. 3 901 769 Dated Auqust 26 1975 Invcntor(s) YASUSHI TAKATORI ET AL It is certified that error appears in the above-identified patent and that said Letters Pe. tent are hereby corrected as shown below:

Column 2, line 40, change "thereof" to --thereon-.

Column 6, line 52, change (Kxblai Al Si O .l0H O" to Column 13, line 16, delete "in" Column 14, line 38, change "Sieve 13" to S ieve'-l3X'-.

Column 19 line 30, the formulashould read as follows;

Column 21, line 25 change "compp'ound to -compound-.

Column 21, line 50, change "crosslinkd" to -cross-linke 1 Signed and Scaled this [SEAL] Sixth y of January 1976 Arrest:

RUTHVC. MASON C. MARSHALL DANN Atleslmg ()jjlrer (ummissimmr of Pare/11s and Trademarks 

1. IN AN ELECTRICAL RECORDING MEMBER PROVIDED WITH A RECORDING LAYER CONTAINING AN IMAGE-FORMING AGENT, AN ELECTRICALLY-CONDUCTIVE AGENT AND A BINDER THERFOR, THE IMPROVEMENT COMPRISING SAID ELECTRICALLYCONDUCTIVE AGENT COMPRISING AT LEAST A POROUS COMPOUND CONTAINING THEREIN A POLAR SUBSTANCE WHEREIN AN IMAGE IF FORMED ON SAID RECORDING LAYER BY THE APPLICATION THERETO OF ELECTRICAL CURRENT.
 2. The electrical recording member according to claim 1, wherein said recording layer is a single layer comprising said image-forming agent, electrically-conductive agent and binder.
 3. The electrical recording member according to claim 1, wherein said recording layer comprises an electrically-conductive layer containing said electrically-conductive agent and an image-forming layer containing said image-forming agent.
 4. The electrical recording member according to claim 1, wherein said image-forming agent comprises a porous compound containing therein a polar substance.
 5. The electrical recording member according to claim 1, wherein said porous compound is at least one member selected from the group consisting of ion-exchange resins, electron-exchange resins, hydrophilic cross-linked polymers, porous polyester resins, and microporous bodies of condensed copolymer resins of dichlorodiphenylsulfone and bisphenol, and wherein said polar substance is at least one member selected from the group consisting of polar solvents, inorganic electrolytes, and organic electrolytes.
 6. The electrical recording member according to claim 1, wherein said porous comppound is at least one member selected from the group consisting of silicic acid, silicates, aluminosilicates and basic aluminum magnesium carbonates, and wherein said polar substance is at least one member selected from the group consisting of polar solvents, inorganic electrolytes and organic electrolytes.
 7. The electrical recording member according to claim 1, wherein the content of said electrically-conductive agent in said recording layer ranges from 30 to 90% by weight based on the total weight of said recording layer.
 8. The electrical recording member according to claim 5, wherein said ion-exchange resin is a porous high polymer selected from the group consisting of polystyrene amine, phenol methylene sulfonic acid, polystyrene sulfonic acid, phenol formaldehyde polyamine, methacrylic acid and vinyl polymers containing an ion-exchangeable acid or base group.
 9. The electrical recording member according to claim 5, wherein said electron-exchange resin is a porous polymer selected from the group consisting of polyvinyl hydroquinone, hydroquinone-formaldehyde resins and dioxyphenyl alanine polymers.
 10. The electrical recording member according to claim 5, wherein said hydrophilic cross-linkd polymer is a porous ternary copolymer of (a) 60 to 90% by weight, based on the weight of the copolymer, of a heterocyclic-N-vinyl monomer; (b) from 40 to 10% by weight, based on the weight of the copolymer, of vinyl acetate or methyl methacrylate; and (c) from 0.5 to 12% by weight, based on the total weight of (a) and (b), of polyethylene glycol dimethacrylate.
 11. The electrical recording member according to claim 5, wherein said porous polyester resin is a resin produced by a process which comprises: a. preParing an oil-in-water emulsion of a polymerizable organic liquid consisting of (1) a polyester of a polycarboxylic acid and a polyhydric alcohol and having at least one functional group of the formula -COCH CH-CO-, and (2) a low molecular weight, polymerizable monomer copolymerizable with (1) and capable of containing therein a low molecular weight, polymerizable non-liquid monomer; in the presence of at least one inorganic metal compound of low solubility in water; and b. subjecting said emulsion to block-polymerization.
 12. The electrical recording member according to claim 5, wherein said microporous body is produced by a process which comprises: a. forming a flat sheet of a uniformly-mixed solution consisting essentially of a condensed copolymer resin of dichlorodiphenylsulfone and bisphenol, chloroform and an alcohol having 1 to 5 carbon atoms; and b. subjecting the resulting flat sheet to volatilization and drying at a temperature below the softening point of the resin.
 13. The electrical recording member according to claim 5, wherein said polar solvent is selected from the group consisting of water, an alcohol, ammonia and dimethylformaldehyde; wherein said inorganic electrolyte is selected from the group consisting of the hydroxides, chlorides, iodides and bromides of alkali metals and alkaline earth metals; and wherein said organic electrolyte is selected from the group consisting of sulfuric acid derivatives, phosphoric acid derivatives, alkylamine salts, cyclic amine salts, amideamine salts, esteramine salts, quaternary ammonium salts and salts obtained by reacting maleic anhydride with an alkylamine.
 14. The electrical recording member according to claim 6, wherein said silicate is a naturally-occurring amorphous or crystalline silicate.
 15. The electrical recording member according to claim 6, wherein said aluminosilicate is represented by the formula: M 2, (M 1)2 . O . Al2O3 . mSiO2 . nH2O wherein M represents a divalent or monovalent metal ion, m is from 3 to 10 and n is a positive number.
 16. The electrical recording member according to claim 14, wherein said aluminosilicate is a natural or synthetic zeolite.
 17. The electrical recording member according to claim 6, wherein said basic aluminum magnesium carbonate is represented by the formula: MgxAly(OH)2x 3y 2z(CO3)z . aH2O wherein x, y and z are integers which satisfy the relationships
 18. The electrical recording member according to claim 6, wherein said polar solvent is selected from the group consisting of water, an alcohol, ammonia and dimethylformaldehyde; wherein said inorganic electrolyte is selected from the group consisting of the hydroxides, chlorides, iodides and bromides of alkali metals and alkaline earth metals; and wherein said organic electrolyte is selected from the group consisting of sulfuric acid derivatives, phosphoric acid derivatives, alkylamine salts, cyclic amine salts, amideamine salts, esteramine salts, quaternary ammonium salts and salts obtained by reacting maleic anhydride with an alkylamine.
 19. The electrical recording member according to claim 1, comprising said recording layer on a base composed of an electrically-conductive material or an electrically-insulating material having an electrically-conductive surface.
 20. The electrical recording member of claim 1, wherein said porous compound has said polar substance impregnated therein in aN amount of from 10 to 75% by weight.
 21. The electrical recording member of claim 1, wherein said image-forming agent is a material capable of forming an image in response to the application of electrical current thereto, and is selected from the group consisting of an oxidation-type color former, a reduction type color former, a pH indicator and a heat-sensitive color former.
 22. The electrical recording member according to claim 1, wherein said recording layer consists essentially of an image-forming agent, said electrically-conductive agent and a binder therefor.
 23. A process for recording an image on an electrical recording member which comprises applying electrical current to a recording layer thereof, thereby forming the image on the recording layer which comprises an image-forming agent, an electrically-conductive agent composed of a porous compound containing therein a polar substance and a binder therefor.
 24. The process for recording an image according to claim 22, wherein said porous compound is at least one member selected from the group consisting of ion-exchange resins, electron-exchange resins, hydrophilic cross-linked polymers, porous polyester resins, and microporous bodies of condensed copolymer resins of dichlorodiphenylsulfone and bisphenol, and wherein said polar substance is at least one member selected from the group consisting of polar solvents, inorganic electrolytes, and organic electrolytes.
 25. The process for recording an image according to claim 23, wherein said porous compound is at least one member selected from the group consisting of silicic acids, silicates, aluminosilicates, and basic aluminum magnesium carbonates, and wherein said polar substance is at least one member selected from the group consisting of polar solvents, inorganic electrolytes, and organic electrolytes.
 26. The process for recording an image according to claim 23, wherein said electrical current is applied to said recording layer through a stylus.
 27. The process for recording an image according to claim 23, wherein said electrical recording member comprises said recording layer on a base composed of an electrically-conductive material or an electrically-insulating material having an electrically-conductive surface. 